pkg/ioutils/readers.go
Nalin Dahyabhai dff96cdeb2 Remove pkg/ioutils.cancelReadCloser
Remove pkg/ioutils's cancelReadCloser type and the vendored copy of
golang.org/x/net/context which it needed, neither of which was used
anywhere else in here.  This should let us sidestep any potential
incompatibilities with the standard library's context package, which was
introduced in golang 1.7.

Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>
2017-03-06 14:00:16 -05:00

83 lines
1.5 KiB
Go

package ioutils
import (
"crypto/sha256"
"encoding/hex"
"io"
)
type readCloserWrapper struct {
io.Reader
closer func() error
}
func (r *readCloserWrapper) Close() error {
return r.closer()
}
// NewReadCloserWrapper returns a new io.ReadCloser.
func NewReadCloserWrapper(r io.Reader, closer func() error) io.ReadCloser {
return &readCloserWrapper{
Reader: r,
closer: closer,
}
}
type readerErrWrapper struct {
reader io.Reader
closer func()
}
func (r *readerErrWrapper) Read(p []byte) (int, error) {
n, err := r.reader.Read(p)
if err != nil {
r.closer()
}
return n, err
}
// NewReaderErrWrapper returns a new io.Reader.
func NewReaderErrWrapper(r io.Reader, closer func()) io.Reader {
return &readerErrWrapper{
reader: r,
closer: closer,
}
}
// HashData returns the sha256 sum of src.
func HashData(src io.Reader) (string, error) {
h := sha256.New()
if _, err := io.Copy(h, src); err != nil {
return "", err
}
return "sha256:" + hex.EncodeToString(h.Sum(nil)), nil
}
// OnEOFReader wraps an io.ReadCloser and a function
// the function will run at the end of file or close the file.
type OnEOFReader struct {
Rc io.ReadCloser
Fn func()
}
func (r *OnEOFReader) Read(p []byte) (n int, err error) {
n, err = r.Rc.Read(p)
if err == io.EOF {
r.runFunc()
}
return
}
// Close closes the file and run the function.
func (r *OnEOFReader) Close() error {
err := r.Rc.Close()
r.runFunc()
return err
}
func (r *OnEOFReader) runFunc() {
if fn := r.Fn; fn != nil {
fn()
r.Fn = nil
}
}